7
Dival SQD-1 - MT 234-E - 02-2020
EN
DESCRIPTION
In fact, this solution allows the diaphragm protection disc 20 to rest on the upper stroke end V1 exceeding
the load of the spring 42 and thus releasing the obturator from the load resulting from the sudden pressure
increase.
In order to prevent small leaks at null required flow rate or that sudden and temporary overpressures, re
-
sulting for example from fast manoeuvres or gas overheating, may let the slam-shut valve trip, the solution
shown by fig. 2a can be transformed, upon request, into an embedded relief valve, eliminating the O-ring
73 and adding the ring 70 (fig. 2b).
Its operation is described as follows: with closed regulator, any overpressures lift the diaphragm protection
disc 20 exceeding the load of the springs 42 and 43. In this way, a given quantity of gas is discharged through
the seat Z of the relief valve.
A
A
19
19
13
13
43
43
28
28
34
34
9
9
33
22
33
33
46
46
48
48
166
166
566
566
V1
V1
SQD-1 Pressure regulator:
Fig. 1
